Kiley
Kiley is most often an Irish surname, generally understood as a form of Kiely, from an old Gaelic personal name.
The #5,255 most common surname in the United States (2010 Census) — about 1 in every 46,505 Americans shares it.
Etymology
Kiley is usually treated as an Anglicized spelling of the Irish surname Kiely, itself from Gaelic personal-name forms such as Ó Cadhla or a related name tradition. The Gaelic root is commonly explained as meaning something like “graceful,” “handsome,” or “beautiful,” though older sources do not always agree on the exact original form. In English records the surname appears in several spellings, with Kiley, Kiely, and related forms often overlapping.
History
Irish surnames of this type were heavily reshaped by English spelling, so Kiley and Kiely can appear as close variants in records rather than fully separate names. Nineteenth-century surname collections list Kiley alongside Kiely, suggesting the two were already being treated as related forms. The name is found chiefly in Irish and Irish-American contexts.
Origin
Regions
Variant spellings
Fun fact
Older surname indexes often file Kiley and Kiely together, which is a clue that historical spelling was fluid rather than fixed.
From the historical record
“Kiely. Kiley. KEENAN. Cainan. 281.”
— Varieties and Synonymes of Surnames and Christian Names in Ireland